Usually a headache is just a headache, and heartburn is nothing more than a sign that you rang the Taco Bell once too often. Except when they’re not.

Pain is your body’s way of telling you that something isn’t quite right. More often than not, you have some idea of what’s behind it. But when it comes on suddenly, lingers longer than usual, or just seems different, it calls for medical attention–and the sooner, the better. According to our experts, all of the following pain conditions should be considered red flags

1. Chest pain
“If patients were to become well versed in what I think of as the subtle language of the heart, many could avoid needless worry and expense,” notes Arthur Agatston, MD, a preventive cardiologist. “Studies have found that women experience a wider range of heart attack symptoms than men do.” In Agatston’s experience, there are three good indicators that something isn’t right, and they can occur in either gender. They are chest pain that doesn’t go away, varied shortness of breath, and any upper body pain that hasn’t occurred before. If you experience any of these symptoms, he says, you should call your doctor or 911 immediately.

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2. Severe head pain
Chances are, it’s a migraine. But if it isn’t accompanied by other migraine symptoms (such as a visual aura), sudden, severe head pain can signal a brain aneurysm. “A burst aneurysm can cause brain damage within minutes, so you need to call 911 immediately,” advises Elsa-Grace Giardina, MD, a cardiologist and director of the Center for Women’s Health at New York-Presbyterian Hospital/Columbia University Medical Center.

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3. A throbbing tooth
It’s likely that the tooth’s nerve has become damaged, probably because the surrounding pearly white enamel is cracked or rotting away. Unless you get it patched up quickly, bacteria in your mouth can invade the nerve. And you definitely don’t want that breeding colony to spread throughout your body, says Kimberly Harms, DDS, a dentist outside St. Paul, Minnesota. If your tooth is already infected, you’ll require a root canal, in which the tooth’s bacteria-laden pulp is removed and replaced with plastic caulking material.

4. Sharp pain in your side
You may just need some Beano. But if you feel as if you’re being skewered in your right side, and you’re also nauseated and running a fever, you could have appendicitis. For women, another possibility is an ovarian cyst. Typically these fluid-filled sacs are harmless and disappear on their own. But if one twists or ruptures, it can cause terrible pain.

In both cases, you’re looking at emergency surgery. “If you don’t remove an inflamed appendix, it can burst,” says Lin Chang, MD, a gastroenterologist and co-director of the Center for Neurovisceral Sciences and Women’s Health at UCLA. A twisted cyst also needs to be removed right away, as it can block blood flow to the ovary within hours.

5. Abdominal discomfort with gas or bloating
For the past month, you’ve felt gassy and bloated more days than not, and it takes fewer slices of pizza to fill you up than it once did. If the symptoms are new, the worst-case scenario is ovarian cancer. In 2007, the Gynecologic Cancer Foundation released the first national consensus on early symptoms of this form of cancer: bloating, pelvic or abdominal pain, and difficulty eating. If you start experiencing them almost daily for more than two or three weeks, consider it a red flag. Schedule an appointment with your ob-gyn to discuss your symptoms.

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6. Back pain with tingling toes
If you’ve just helped your cousin move into her new fourth-floor apartment, anti-inflammatories should banish the pain. But if they don’t work, hobble to an orthopedist. “One of your discs (the spongy rings that cushion the bones in your spine) could be pressing on the spinal nerve,” says Letha Griffin, MD, an orthopedist and sports medicine specialist in Atlanta. Without proper attention, you risk permanent nerve damage.

7. Leg pain with swelling
Your calf is extremely tender in one location, noticeably swollen, and red or warm to the touch. You might have deep-vein thrombosis (DVT), commonly known as a blood clot. Resist the urge to massage the area or to try walking off the pain. If the clot breaks free, it can travel through your veins up to your lungs and cut off your oxygen supply. Instead, see your doctor right away. He or she will do a CT scan or ultrasound to check for a DVT. If that’s what you have, you’ll need to take blood thinners–sometimes for up to a year–to dissolve it, says Suzanne Steinbaum, MD, director of women and heart disease for the Heart and Vascular Institute at Lenox Hill Hospital in New York City.